for testing purposes, I have set up 2 Pis on a local lan.

Transmitting PI has usb sound card and openob uses alsa invoked like this:

/usr/local/bin/openob 192.168.86.149 test-tx-node test-link tx -a alsa -d hw:1 192.168.86.149

aplay -l gives:

card 1: CODEC [USB AUDIO  CODEC], device 0: USB Audio [USB Audio]
  Subdevices: 1/1
  Subdevice #0: subdevice #0

Receiving Pi uses onboard sound card and openob uses jack invoked like this:

/usr/local/bin/openob 192.168.86.149 test-rx-node test-link rx -a jack -jn openob -aj -jp jack_mixer:ICh2

It is also running jack-mixer and a few other toys.

After hooking things up as desired in qjackctl, I see the mono audio in jack-mixer and hear it in my headphones plugged into the Pi's soundcard.

Any thoughts on how to track down the mono issue?

all the best,

drew

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